Methodological Individualism

Why methodological individualism? 327that both theories may be reduced to each other, the only difference being theirvocabulary. 7An important point made by Kemeny and Oppenheim, however, is thatactual scientific reductions are seldom strict derivations. This point has recurredin the later critique of Nagel’s approach to reduction, and especially, in thecritique by Paul Feyerabend. According to Feyerabend, most cases taken fromthe history of science and cited as examples of reduction do, in fact, show thatthe ‘reduced’ theory is not derivable from, but inconsistent with, the ‘reducing’theory. It is a matter of replacement rather than of inclusion. What can bederived from the primary theory is, at best, an approximation to the secondarytheory (Feyerabend, 1962: 43–8).Confronted with this critique, Schaffner suggests a new approach to reduction,which retains the basic idea of Nagel while incorporating the critique ofFeyerabend. According to Schaffner, what must be derivable from the primarytheory is not the original secondary theory, but a corrected version of thesecondary theory. The primary theory, furthermore, must be able to indicate inwhat respect the secondary theory is incorrect, and why it worked as well as itdid. Reduction, then, becomes a combination of replacement and inclusion.Concerning the status of the connecting link between the terms of the primaryand secondary theories, Schaffner suggests that they are synthetic identities(Schaffner, 1967: 144).This concludes my presentation of the different approaches to reduction. Butthere are also different types of reduction. Nagel mentioned two, homogeneousand heterogeneous reduction, and among heterogeneous reductions, especiallythose which involve phenomena that are microscopic relative to some other,macroscopic phenomena. Reductions of this type have become known as ‘microreductions’.Micro-reduction has been discussed by, among others, Oppenheimand Putnam (1958). 8 According to them, the essential feature of a microreductionis that the objects dealt with by the primary science are parts of theobjects dealt with by the secondary science. For their general concept of ‘reduction’,Oppenheim and Putnam rely on Kemeny and Oppenheim (see above).One advantage with micro-reduction is that it affords asymmetry to theKemeny–Oppenheim approach. Another advantage, according to Oppenheimand Putnam, is that it helps to bring about the ideal of a unitary science, in thestrong sense of unity of laws (Oppenheim and Putnam, 1958: 6–8).The idea of micro-reduction is part of a more comprehensive view of theuniverse as organised into a hierarchy of reductive levels, where each level is theproper domain of a scientific branch or discipline. The perfect reduction wouldbe accomplished if all sciences could be reduced to the science dealing withobjects at the lowest level, that is to physics. Oppenheim and Putnam entertainthe possibility of realising this ideal as a working hypothesis. A first step in therealisation of this ideal is the reduction of theories about social groups to theoriesabout ‘living things’, of which human beings is a sub-class. In support oftheir working hypothesis, Oppenheim and Putnam cite, not surprisingly, theexamples of Mill, Weber and economic theory, but, more surprisingly, also Marx